Think it has been mentioned in this thread before but in case anyone not aware - travelling up to a weeknight game anytime after about 3.30pm, it's much much cheaper to travel from Euston via Nuneaton on the way up. The 16.46 to Nuneaton tomorrow is still only £18 (think the advance tickets first go on sale for £6) and can get from nuneaton to leicester for less than a fiver.
That route has saved me hundreds of pounds compared to what would have paid going direct to Leicester on-peak